Cirrus Logic CobraNet Audio Routing Primer User Manual

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Appendix A - MI Variables used in routing

Refer to the CobraNet

Programmer’s Reference for more detailed information on these variables.

txBundle
rxBundle:

Array variables which set the bundle number that a transmitter or receiver will use. There is one
instance of these variables for each Receiver or Transmitter.

Defaults:

All variables = 0 for standard CobraNet

interfaces.

May be initialized to other values depending on product.

txSubMap:

An array variable which maps which Audio Routing Channel goes to which bundle sub-channel.
There are multiple instances of this variable for each transmitter.

Defaults:

Transmitter 1 = 1 -> 8

Transmitter 2 = 9 -> 16

Transmitter 3 = 17 -> 24

Transmitter 4 = 25 -> 32

rxSubMap:

An array variable which maps which bundle sub-channel goes to which Audio Routing Channel.
There are multiple instances of this variable for each receiver.

Defaults:

Receiver 1 = 32 -> 40

Receiver 2 = 41 -> 48

Receiver 3 = 49 -> 56

Receiver 4 = 57 -> 64

txSubFormat:

An array variable which sets the audio format of each bundle sub-channel. There are multiple
instances of this variable for each transmitter.

Default:

0x54000 = 5-1/3 mS latency, 48KHz sample rate, 20 bit sample size

rxSubFormat

As above for txSubFormat except for the following:

• rxSubFormat is Read only

• The LSB will be set to 1 when the audio channel is being properly decoded. If LSB is seen

set to 0, then the interface recognizes the format but cannot decode it (probably due to an
incompatible modeRateControl value).

Default:

N.A.; Set based on format of received sub-channel

txSubCount:

An array variable which sets the number of sub-channels contained in a bundle. Fewer than the
maximum number of channels allowable can be specified. This value must be greater than or equal
to the number of channels to be sent in a bundle. There is one instance of this variable per
Transmitter.

Default:

CobraNet

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